Advancements in electronics technology have allowed electronic equipment, such as computers, to be downsized to facilitate portability. This downsizing has resulted in internal spatial restrictions that have created a need for the establishment of standards for the component devices in the electronic equipment.
The Personal Computer Memory Card International Association (PCMCIA), an organization comprised of hundreds of manufacturers of memory cards and related peripheral equipment, has established spatial standards for all circuit boards used in downsized computers. PCMCIA has developed a 68-pin memory card standard for three memory card types as follows:
a. Type I Memory Cards are the same width and length as a common credit card, about 54 mm.times.85.6 mm, but are thicker than a credit card. The thickness of a Type I card is 3.3 mm (0.130"). PA1 b. Type II Memory Cards are used by those companies which are utilizing memory components that are too high to be housed within a Type I card. Type II memory cards are also the same overall length and width as credit cards, but have a raised body cross section in the substrate area which gives them an overall thickness of 5 mm (0.195"). The raised substrate areas of these cards are 48 mm in width. PA1 c. Type III Memory Card are the result of a recent movement sponsored by the Small Form Factor Committee to enable 1.8" Small Form Factor Disk Drives to be plugged into memory card connectors in small portable computer applications. Type III memory cards are the same length and width as Type I and Type II memory cards. However, Type III cards have a substrate area thickness of 10.5 mm. Also, Type III memory cards require a card guide opening width of 51 mm on the header connector to accommodate the slightly wider raised substrate area.
By complying with the standards established by PCMCIA for memory cards, card manufacturers of peripheral devices, such as communication cards, have assured themselves of compatibility and spatial conformity with computers and other electronic devices that conform to the new PCMCIA standards. The size and shape of the circuit board holder of the present invention complies with the PCMCIA Type II memory card standards. The standard 68-pin connector is plugged into a keyed plug connector on a computer or electronic device and the dimensions of the card holder frame and covers are standard for Type II cards. However, the novel grounding, heat sinking and electrostatic discharge resistance features of the present invention are not limited to PCMCIA Type II memory cards and can be used for PCMCIA Type I and Type III memory cards as well as other circuit boards for computer or electronic devices.
Bar code scanners are widely used at check-out counters in supermarkets, department stores and almost every other business where a cash register is employed. The scanners are typically mounted in either a stationary housing or a hand held "gun" or "wand" that is connected to the computerized register with an electrical cord. A major limitation with these scanners is that they are tethered to the register and cannot be used outside of a short distance from a relatively fixed location. This limitation has created a long felt need in the bar code industry for portable bar code scanners. The present invention meets this need by providing a portable bar code scanner that interfaces with a cash register or other computerized device by radio communication.
The present invention provides for a PCMCIA Type II card holder with a circuit board for a spread spectrum radio communicator that overcomes all Radio Frequency Interference (RFI) shielding, Electrostatic Discharge (ESD) resistance and heat-sinking problems encountered by typical prior art devices. However, this memory card holder is not limited to spread spectrum communicators and may be used for various types of memory cards and circuit boards. The present invention is specifically designed to provide radio communication between portable bar-code scanners and other data collecting and/or generating devices through a local-area network to a computer. This satisfies a long felt need for communications between a portable scanner and other similar devices and a stationary computer. Such time consuming tasks as taking inventory in a warehouse or other facility are made simpler, easier and faster by the present invention. The present invention, when used with a local-area network installed within the facility, enables a scanner or other device to communicate directly with the computer that manages the inventory. Other uses include monitoring articles as they enter and leave an area and tracking manufacturing production by monitoring articles at various stages of the production process.
In the prior art, communication was typically accomplished by hard-wired interconnection between a remote device and a computer or by connecting an external radio communicator to the portable device for communication with the computer. Integrally mounting a radio communicator in a portable device required elaborate shielding methods since the proximity of other electronic components in the spatially restricted housings resulted in the disruption of the radio communication signal. In addition to the digital noise generated from within the housing, these radio communicators also were susceptible to disruption from external noise. These problems were not successfully overcome by typical prior art communicators because the spatial restrictions did not permit adequate room for shielding and grounding.